1. Field of the Invention
This invention relates to a power conversion circuit and a power conversion circuit system, and, more particularly, to a power conversion circuit having a plurality of input/output ports, and a power conversion circuit system including the power conversion circuit.
2. Description of the Related Art
It may be desired that, in a power conversion circuit having a plurality of input/output ports, electric power is converted between two input/output ports among the plurality of input/output ports. For example, Patent Document 1 (U.S. Pat. No. 7,408,794) discloses a DC-DC converter circuit which includes three input/output ports and a half bridge circuit. It is further disclosed that a high voltage inverter circuit, a 14V load, and a 42V load are connected to the three input/output ports of the DC-DC converter circuit.
Meanwhile, Patent Document 2 (JP A 2006-187147) discloses a DC-DC converter circuit which includes two input/output ports and a full bridge circuit. In addition to reactors constituting a transformer, three other reactors are provided in the DC-DC converter circuit. It is also disclosed that a high voltage inverter circuit and a low voltage electronic device are connected to the two input/output ports of the DC-DC converter circuit.
Although the above Patent Document 1 discloses that electric power is converted using the three input/output ports, the DC-DC converter circuit is low in electric capacitance, and limited in its range of adaptable application due to a configuration of using the half bridge circuit. Therefore, Patent Document 1 does not disclose power conversion between two input/output ports selected from among three or more input/output ports. That is, Patent Document 1 provides no disclosure of a specific way of converting electric power between two input/output ports selected from four input/output ports.
Meanwhile, the above Patent Document 2 discloses power conversion using the two input/output ports, and the DC-DC converter circuit of Patent Document 2 is high in electric capacitance and broader in its range of adaptable application, because the DC-DC converter circuit is composed of the full bridge circuit as distinct from the circuit of Patent Document 1. However, the three additional reactors are needed, which might impair a cost merit. In addition, Patent Document 2 includes neither description about two or more input/output ports, nor disclosure of the specific way of converting electric power between two input/output ports selected from four input/output ports.